Gliese 86

Gliese 86
Location of Gliese 86 (circled in red)
Observation data
Epoch J2000.0      Equinox ICRS
Constellation Eridanus
Gliese 86 A
Right ascension 02h 10m 25.9182s
Declination −50° 49′ 25.465″
Apparent magnitude (V) 6.17
Gliese 86 B
Right ascension 02h 10m 26.1144s
Declination −50° 49′ 26.334″
Apparent magnitude (V) 14.0
Characteristics
A
Evolutionary stage main sequence
Spectral type K1V
U−B color index 0.44
B−V color index 0.82
B
Evolutionary stage white dwarf
Spectral type DQ6
Astrometry
A
Radial velocity (Rv)+55.22±0.15 km/s
Proper motion (μ) RA: +2,125.416 mas/yr
Dec.: +637.975 mas/yr
Parallax (π)92.9251±0.0461 mas
Distance35.10 ± 0.02 ly
(10.761 ± 0.005 pc)
Absolute magnitude (MV)5.95
Orbit
PrimaryGliese 86 A
SecondaryGliese 86 B
Period (P)≈100 yr
Semi-major axis (a)23.7 au
Eccentricity (e)0.429
Inclination (i)126.44°
Longitude of the node (Ω)234.2°
Details
Gliese 86 A
Mass0.83±0.05 M☉
Radius0.79±0.03 R☉
Luminosity0.41 L☉
Surface gravity (log g)4.56±0.10 cgs
Temperature5,180±80 K
Metallicity [Fe/H]−0.27±0.07 dex
Rotation30.0 days
Rotational velocity (v sin i)2.0±1.0 km/s
Age10±1 Gyr
Gliese 86 B
Mass0.5425 M☉
Radius0.012 R☉
Surface gravity (log g)8.02 cgs
Temperature8,180±200 K
Other designations
GJ 86, WDS J02104-5049
Gliese 86A: CD−51°532, HD 13445, HIP 10138, HR 637, SAO 232658
Gliese 86B: WD 0208-510
Database references
SIMBADdata
B
Exoplanet Archivedata
ARICNSdata

Gliese 86 (13 G. Eridani, HD 13445) is a K-type main-sequence star 35 light-years away in the constellation of Eridanus. It has been confirmed that a white dwarf orbits the primary star. In 1998 the European Southern Observatory announced that an extrasolar planet was also orbiting the star.

Stellar components

The primary companion (Gliese 86 A) is a K-type main-sequence star of spectral type K1V. The characteristics in comparison to the Sun are 83% the mass, 79% the radius, and 50% the luminosity. The star has a close-orbiting massive Jovian planet.

Gliese 86 B is a white dwarf located around 21 AU from the primary star, making the Gliese 86 system one of the tightest binaries known to host an extrasolar planet. It was discovered in 2001 and initially suspected to be a brown dwarf, but high contrast observations in 2005 suggested that the object is probably a white dwarf, as its spectrum does not exhibit molecular absorption features which are typical of brown dwarfs. Assuming the white dwarf has a mass about half that of the Sun and that the linear trend observed in radial velocity measurements is due to Gliese 86 B, a plausible orbit for this star around Gliese 86 A has a semimajor axis of 18.42 AU and an eccentricity of 0.3974. When both stars were on the main sequence, the separation between the two stars was closer, at around 9 AU. More precise measurements for the white dwarf give it a mass of 55% the mass of the Sun and a temperature of around 8200 K. It is likely to have been an A5 star when on the main sequence.

Planetary system

The planet Gliese 86 b was discovered by the Swiss 1.2 m Leonhard Euler Telescope operated by the Geneva Observatory. Such an object was formed from a protoplanetary disk that was truncated at 2 AU from the parent star.

The radial velocity measurements of Gliese 86 show a linear trend once the motion due to this planet are taken out. This may be associated with the orbital motion of the white dwarf companion.

The Gliese 86 A planetary system
Companion
(in order from star)		 Mass Semimajor axis
(AU)		 Orbital period
(days)		 Eccentricity Inclination
(°)		 Radius
b ≥6.588±0.018 MJ 0.114340±0.000001 15.76480±0.00004 0.048±0.002 — —

See also

References

  1. ↑ Roman, Nancy G. (1987). "Identification of a constellation from a position". Publications of the Astronomical Society of the Pacific. 99 (617): 695. Bibcode:1987PASP...99..695R. doi:10.1086/132034. Constellation record for this object at VizieR.
  2. 1 2 3 4 5 6 7 Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
  3. ↑ C. Cincunegui; P. J. D. Mauas (2004). "Library of flux-calibrated echelle spectra of southern late-type dwarfs with different activity levels". Astronomy and Astrophysics. 414 (2): 699–706. Bibcode:2004A&A...414..699C. doi:10.1051/0004-6361:20031671. hdl:11336/21158.
  4. 1 2 Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
  5. ↑ Holberg, J. B.; Oswalt, T. D.; Sion, E. M.; McCook, G. P. (2016). "The 25 parsec local white dwarf population". Monthly Notices of the Royal Astronomical Society. 462 (3): 2295. Bibcode:2016MNRAS.462.2295H. doi:10.1093/mnras/stw1357.
  6. ↑ Gray, R. O.; et al. (July 2006), "Contributions to the Nearby Stars (NStars) Project: spectroscopy of stars earlier than M0 within 40 pc-The Southern Sample", The Astronomical Journal, 132 (1): 161–170, arXiv:astro-ph/0603770, Bibcode:2006AJ....132..161G, doi:10.1086/504637.
  7. 1 2 Karataş, Y.; Schuster, W. J. (2006). "Metallicity and absolute magnitude calibrations for UBV photometry". Monthly Notices of the Royal Astronomical Society. 371 (4): 1793. Bibcode:2006MNRAS.371.1793K. doi:10.1111/j.1365-2966.2006.10800.x.
  8. 1 2 Mugrauer, M.; Neuhäuser, R. (2005). "Gl86B: a white dwarf orbits an exoplanet host star". Monthly Notices of the Royal Astronomical Society: Letters. 361 (1): L15–L19. arXiv:astro-ph/0506311. Bibcode:2005MNRAS.361L..15M. doi:10.1111/j.1745-3933.2005.00055.x. S2CID 16904466.
  9. 1 2 3 4 5 Farihi, J.; Bond, Howard E.; Dufour, P.; Haghighipour, N.; Schaefer, G. H.; Holberg, J. B.; Barstow, M. A.; Burleigh, M. R. (2013). "Orbital and evolutionary constraints on the planet hosting binary GJ 86 from the Hubble Space Telescope". Monthly Notices of the Royal Astronomical Society. 430 (1): 652. arXiv:1212.5601. Bibcode:2013MNRAS.430..652F. doi:10.1093/mnras/sts677.
  10. ↑ Holmberg, J.; et al. (July 2009), "The Geneva-Copenhagen survey of the solar neighbourhood. III. Improved distances, ages, and kinematics", Astronomy and Astrophysics, 501 (3): 941–947, arXiv:0811.3982, Bibcode:2009A&A...501..941H, doi:10.1051/0004-6361/200811191.
  11. 1 2 3 4 5 Zeng, Yunlin; Brandt, Timothy D.; Li, Gongjie; Dupuy, Trent J.; Li, Yiting; Brandt, G. Mirek; Farihi, Jay; Horner, Jonathan; Wittenmyer, Robert A.; Butler, R. Paul.; Tinney, Christopher G.; Carter, Bradley D.; Wright, Duncan J.; Jones, Hugh R. A.; o'Toole, Simon J. (2022). "The Gliese 86 Binary System: A Warm Jupiter Formed in a Disk Truncated at ≈2 au". The Astronomical Journal. 164 (5): 188. arXiv:2112.06394. Bibcode:2022AJ....164..188Z. doi:10.3847/1538-3881/ac8ff7. S2CID 252872318.
  12. 1 2 3 4 5 6 7 8 Fuhrmann, K.; et al. (2014). "On the Age of Gliese 86". The Astrophysical Journal. 785 (1). 68. Bibcode:2014ApJ...785...68F. doi:10.1088/0004-637X/785/1/68.
  13. ↑ Reiners, Ansgar; Zechmeister, Mathias (2020). "Radial Velocity Photon Limits for the Dwarf Stars of Spectral Classes F-M". The Astrophysical Journal Supplement Series. 247 (1): 11. arXiv:1912.04120. Bibcode:2020ApJS..247...11R. doi:10.3847/1538-4365/ab609f.
  14. ↑ Cruz Aguirre, Fernando; Youngblood, Allison; France, Kevin; Bourrier, Vincent (2023). "Disentangling Stellar and Airglow Emission Lines from Hubble Space Telescope (HST) Cosmic Origins Spectrograph (COS) Spectra". The Astrophysical Journal. 946 (2): 98. Bibcode:2023ApJ...946...98C. doi:10.3847/1538-4357/acad7d.
  15. ↑ "HD 13445". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2020-08-14.
  16. ↑ "HD 13445B". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2020-08-14.
  17. ↑ "Extrasolar Planet in Double Star System Discovered from La Silla" (Press release). Garching, Germany: European Southern Observatory. November 24, 1998. Archived from the original on May 21, 2020. Retrieved December 29, 2012.
  18. ↑ Raghavan, Deepak; et al. (2006). "Two Suns in The Sky: Stellar Multiplicity in Exoplanet Systems". The Astrophysical Journal. 646 (1): 523–542. arXiv:astro-ph/0603836. Bibcode:2006ApJ...646..523R. doi:10.1086/504823.
  19. ↑ Els, S. G.; et al. (2001). "A second substellar companion in the Gliese 86 system. A brown dwarf in an extrasolar planetary system". Astronomy and Astrophysics. 370 (1): L1–L4. Bibcode:2001A&A...370L...1E. doi:10.1051/0004-6361:20010298.
  20. ↑ Lagrange, A.-M.; et al. (2006). "New constrains on Gliese 86 B. VLT near infrared coronographic imaging survey of planetary hosts". Astronomy and Astrophysics. 459 (3): 955–963. Bibcode:2006A&A...459..955L. doi:10.1051/0004-6361:20054710.
  21. ↑ "Southern Sky extrasolar Planet search Programme". Archived from the original on 2020-07-15. Retrieved 2009-02-18.
  22. ↑ Wittenmyer, Robert A.; et al. (2020). "Cool Jupiters greatly outnumber their toasty siblings: occurrence rates from the Anglo-Australian Planet Search". Monthly Notices of the Royal Astronomical Society. 492 (1): 377–383. arXiv:1912.01821. Bibcode:2020MNRAS.492..377W. doi:10.1093/mnras/stz3436. S2CID 208617606.